Auto-immune diseases affect nearly 24 million people in the United States (roughly 8% of the population) alone making it one of the most prevalent diseases. By comparison, heart disease affects 22 million and cancer 9 million. Many auto-immune diseases are correlated with elevated levels of a naturally occurring protein in the body known as tumor necrosis factor (“TNFα”). TNFα is a cytokine capable of inducing fever, cell death and inflammation among other illnesses. TNFα works by binding to and activating cell surface receptors which lead to the activation of genes involved in inflammation.
Adalimumab is an anti-inflammatory drug targeted to inhibiting TNFα from binding to these cell surface receptors. Adalimumab is the first fully human monoclonal antibody approved by the United States Food and Drug Administration (“FDA”) and is sold by AbbVie Biotechnology LTD under the trademark Humira® (Humira is a registered trademark of AbbVie Biotechnology LTD). Humira® has been approved by the FDA for several auto-immune diseases including rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn's disease, ulcerative colitis, moderate to severe chronic psoriasis and juvenile idiopathic arthritis.
Methotrexate is also approved by the FDA for the treatment of various auto-immune diseases. Adalimumab has been shown to be more effective than methotrexate for the treatment of certain auto-immune diseases. The combination of adalimumab and methotrexate shows an even greater improvement in symptoms of auto-immune disease over the use of either one alone. One problem facing patients suffering from auto-immune diseases that could benefit from adalimumab or a combination therapy is the cost. Adalimumab can cost from $2,500 to $5,000 per month whereas methotrexate can cost as little as $30 per month. One reason that adalimumab has a higher cost is that it is a recombinant protein which must be produced by and harvested from cell culture. Improvements in the cell culture and protein production process can reduce the costs associated with the manufacture of adalimumab (HUMIRA®) and other antibodies including biosimilars, thereby allowing those cost savings to be passed on to patients.
Biosimilar molecules must also exhibit glycosylation patterns similar to the reference molecule. It has surprisingly been found that using a reduced amount of glucose in the cell culture media, together with alternate energy sources, will produce a biosimilar molecule having a glycosylation profile similar to the reference product.
Mammalian cells are routinely cultured in commercially available cell culture media including Dulbecco's Modified Eagle's Medium (DMEM) and Roswell Park Memorial Institute Medium (RPMI). However, for purposes of protein production, these media and the methods by which they are employed can be further modified to increase production. These modifications can be protein specific. Even small improvements in protein production or methods by which those proteins are produced can have a substantial economic impact on the cost of therapeutic recombinant proteins such as adalimumab. Thus, there remains a need in the art for improved methods and compositions of making proteins, in particular anti-TNFα antibodies, via cell culture.